# Installing the hydraulic pump

## Preliminary requirements

### Consumables, materials and expendables

| Name            | Identification/References | Quantity |
| --------------- | ------------------------- | -------- |
| Hydraulic fluid | C-072                     | AR       |
| Packing         | M83461/2-905              | 1        |
| Packing         | M83461/2-908              | 1        |
| Packing         | M83461/1-024              | 1        |

### Safety conditions

{% hint style="warning" %}
Make sure that you only remove the protective caps or plugs immediately before you install the fittings or components. Damage or contamination can occur if you do not obey.
{% endhint %}

## Procedure

1. Remove the protective caps or plugs from the open ends and ports.

{% hint style="info" %}
Hydraulic pumps do not come preserved with MIL-PRF-87257. You must flush the new part before installation.
{% endhint %}

2. To flush the new hydraulic pump, do the steps that follow:
   1. Over a fluid receptacle, fill the pressure port of the hydraulic pump with hydraulic fluid conforming to MIL-PRF-87257.
   2. Turn the hydraulic pump and remove the hydraulic fluid from the pressure port.
   3. Fill the return port of the hydraulic pump with hydraulic fluid conforming to MIL-PRF-87257.
   4. Place a pump driveshaft assembly (M206-20H026) over the input shaft of the hydraulic pump and manually rotate the hydraulic pump counterclockwise until all the hydraulic fluid has drained from the return port.
   5. Do Step 2.3 through Step 2.4, two more times.
3. To install the union fitting on the suction port, if necessary, do the steps that follow:
   1. Apply a layer of Hydraulic fluid (C-072) to the Packing (M83461/2-908).
   2. Install the Packing (M83461/2-908) on the union fitting.
   3. Install the union fitting on the suction port of the hydraulic pump.
   4. Torque the union fitting 210 to 420 inch-pounds (23.7 to 47.5 Nm).
4. To install the union fitting on the pressure port, if necessary, do the steps that follow:
   1. Apply a layer of Hydraulic fluid (C-072) to the Packing (M83461/2-905).
   2. Install the Packing (M83461/2-905) on the union fitting.
   3. Install the union fitting on the pressure port of the hydraulic pump.
   4. Torque the union fitting 85 to 180 inch-pounds (9.6 to 20.3 Nm).

{% hint style="warning" %}
Make sure that the adapter shaft is correctly engaged with the splines of the pumps before the installation of the mounting bolt. If not, damage to the hydraulic pump and transmission oil pump can occur.
{% endhint %}

{% hint style="info" %}
This log book entry is to make sure that you will drain and discard the hydraulic fluid and the hydraulic pressure filter element after the [100 flight hours/1 year inspection](../../../servicing#id-100-flight-hours-1-year-inspection).
{% endhint %}

5. To install a hydraulic pump P/N M206-20H030-043, do as follows:
   1. If you install a new hydraulic pump P/N M206-20H030-043, make an entry in the log book.
   2. Examine the hydraulic pump every [300 flight hours/1 year inspection](../../../servicing#id-300-flight-hours-1-year-inspection) or [1200 flight hours inspection](../../../base-maintenance/servicing), as necessary.
   3. Apply a layer of Hydraulic fluid (C-072) to the Packing (M83461/1-024).
   4. Install the hydraulic pump with the washers and the bolts.
6. For the hydraulic pump P/N M206-20H030-041, install the hydraulic pump with the washers and the bolts.
7. Torque the bolts 100 to 140 inch-pounds (11.3 to 15.8 Nm).
8. Apply a layer of Hydraulic fluid (C-072) on all the threads of hydraulic lines and component connections.
9. Connect the suction hose to the hydraulic pump union fitting.
10. Torque the nut of the suction hose 85 to 180 inch-pounds (9.6 to 20.3 Nm).
11. Connect the filter-to-HRFM pressure line to the hydraulic pump union fitting.
12. Torque the nut of the filter-to-HRFM pressure line 85 to 180 inch-pounds (9.6 to 20.3 Nm).

## Requirements after job completion

### Required Conditions

<table><thead><tr><th>Action/Condition</th><th data-type="content-ref">Reference</th></tr></thead><tbody><tr><td>Fill the hydraulic system with fluid.</td><td><a href="../../servicing/replenishing-and-depleting/filling-the-hydraulic-system-with-fluid">filling-the-hydraulic-system-with-fluid</a></td></tr><tr><td>Install the upper-right mid-fuselage access-panel (433BR).</td><td></td></tr><tr><td>Install the upper-left mid-fuselage access-panel (433AL).</td><td></td></tr><tr><td>Do an operation test of the main hydraulic system.</td><td><a href="../../test-and-checks/testing-the-operation-of-the-hydraulic-system">testing-the-operation-of-the-hydraulic-system</a></td></tr></tbody></table>
